Sulfosuccinate derivatives as detergent builders

ABSTRACT

Novel salts of α-substituted-β-sulfosuccinic acids having the general formula: ##EQU1## wherein R is hydrogen or an organic moiety, Z is selected from the group consisting of O, S, SO, SO 2 , N and NO and M is an alkali metal, ammonium or substituted ammonium cations, useful as detergents and/or detergent builders and detergent compositions containing same.

This is a division, of application Ser. No. 394,613, filed Sept. 5,1973, which in turn is a division of Ser. No. 156,933, filed June 25,1971, now abandoned.

BACKGROUND OF THE INVENTION

Eutrophication is the process of excessive fertilization of aquaticplants through enrichment of waters with nutrients, such as carbon,nitrogen, phosphorus, potassium, iron, trace metals and vitamins.

Although there is no present adequate proof, it has been postulated thatthe phosphorus-containing builders present in detergent compositions canbe a factor in eutrophication. Therefore any substitutes which do notcontain phosphorus may decrease to some extent the eutrophication.

It is therefore an object of the present invention to provide novelcompounds which are useful as detergent builders. It is another objectof the present invention to provide novel compounds which function assurface active agents and as detergent builders. It is still anotherobject of the present invention to provide detergent compositions whichare free of phosphorus-containing builders such as the alkali metalcondensed phosphates.

DESCRIPTION OF THE INVENTION

It has now been discovered that the alkali metal ammonium andsubstituted ammonium salts of certain sulfoaliphatic dicarboxylic acidscan serve as effective detergent builders in detergent compositions. Thedetergent builders and their acid forms employed in accordance with oneembodiment of the present invention can be generally described asα-substituted-β-sulfosuccinic acids and salts thereof having the generalformula: ##EQU2## wherein Z is selected from the group consisting of O,S, SO and SO₂ ; R is selected from the group consisting of hydrogen,alkyl containing 1-30 carbon atoms, phenyl, carboxyl substituted andmono- di- or tri-alkyl substituted phenyl, wherein the alkyl group orgroups contain 1-4 carbon atoms; sulfo- and carboxy-alkyl, wherein thealkyl moiety contains 1-4 carbon atoms; and R'Z(CH₂ CH₂ O)n-CH₂ CH₂ --,wherein R' is H or alkyl containing 1-24 carbon atoms; Z is as above;and n is 0 or an integer of from 1-15 and the alkali metal, ammonium andsubstituted ammonium salts thereof.

Thus, specific compounds and classes of compounds embraced by thegeneric formula above include:

α-hydroxy-β-sulfosuccinic acids

α-alkoxy-β-sulfosuccinic acids

α-phenoxy-β-sulfosuccinic acids

α-carboxyphenoxy-β-sulfosuccinic acids

α-alkylphenoxy-β-sulfosuccinic acids

α-carboxyalkoxy-β-sulfosuccinic acids

α-sulfoalkoxy-β-sulfosuccinic acids

α-alkoxyethoxy-β-sulfosuccinic acids

α-alkoxypolyethyleneoxyethoxy-β-sulfosuccinic acids

α-hydroxyalkoxy-β-sulfosuccinic acids;

the alkali metal, ammonium and substituted ammonium salts thereof; andthe thio, sulfinyl and sulfonyl analogs of all the foregoing compoundswherein the oxygen group attached to the α-carbon of the succinic acidor succinate moiety is replaced by --S--, --SO-- or --SO₂ --,respectively, and/or wherein the cases of the α-alkoxyethoxy compoundsand the α-alkoxypolyethyleneoxyethoxy compounds the oxygen attached tothe alkyl group (R') is replaced by --S--, --SO-- or --SO₂ --.

In accordance with another embodiment of the present invention are thenitrogen containing α-substituted-β-sulfosuccinic acids and saltsthereof having the following general formula: ##EQU3## wherein at leastone of R₁ and R₂ is hydrogen, C₁ to C₂₀ alkyl, C₁ to C₄ hydroxyalkyl,carboxymethyl, carboxyethyl, sulfomethyl and sulfoethyl, or R₁ and R₂may be joined to form a morpholinyl moiety; with the proviso that bothR₁ and R₂ may not at the same time be hydrogen.

Thus, broadly the compounds of Formula I differ from the compounds ofFormula II only in the atom represented by Z.

Representative compounds and classes of compounds embraced by genericFormula II above include:

α-alkylamino-β-sulfosuccinic acids such as α-methylamino, α-propylamino,α-octylamino and α-laurylamino-β-sulfosuccinic acid;

α-dialkylamino-β-sulfosuccinic acids such as α-dimethylamino,α-ethylmethylamino, α-methylhexylamino andα-dioctylamino-β-sulfosuccinic acid;

α-hydroxyalkyl-β-sulfosuccinic acids such as α-hydroxyethylamino,α-hydroxybutylamino and α-bis(hydroxyethyl)amino-β-sulfosuccinic acid;α-carboxyalkylamino-β-sulfosuccinic acids such as α-carboxymethylamino,α-carboxyethylamino-β-sulfosuccinic acid and the corresponding sulfoanalogs;

α-morpholinyl-β-sulfosuccinic acid; and the mono or poly salts thereof.

In accordance with still another embodiment of the present invention arethe amine oxide derivatives of Formula II, wherein the nitrogen is atertiary atom, corresponding to the following general formula: ##EQU4##wherein R₁ and R₂ are as is designated in Formula II with the provisothat neither R₁ nor R₂ can be hydrogen.

As will be appreciated by those skilled in the art, the compounds of theinvention contain at least two asymmetric carbon atoms and therefore canexist in several optically active forms as well as optically inactivemixtures (racemates). For purposes of this invention, the compounds asdefined are intended to include all of the stereoisometric forms andmixtures thereof.

In addition to the detergent building properties exhibited by the entireclass of compounds described above, certain select members also exhibitproperties which make them useful as wetting and foaming agents and thusconstitute a class of novel surface active agents. For example, theα-alkoxy-β-sulfosuccinic acids and the thio analogs, containing fromabout 1-8 carbons, preferably from about 1 to about 4 carbon atoms,exhibit excellent detergent building properties whereas the higherhomologs containing from about 9-30 and more preferably 9-24 carbonatoms in the alkyl chain, additionally exhibit wetting, foaming anddetergency properties.

Similarly, the α-alkoxyethoxy andα-alkoxypolyethyleneoxyethoxy-β-sulfosuccinic acid compounds containingfrom about 9-30 and preferably about 9-24 carbon atoms in the alkoxymoiety are also useful as wetting agents, foaming agents and detergentsas well as detergent builders.

Although the builders of the present invention may be utilized as thefree acid provided sufficient alkaline additives are included in thedetergent composition to convert the acid forms in situ to the normalsalt forms, the alkali metal, ammonium and substituted ammonium salts ofthe α-substituted-β-sulfosuccinic acids are preferred. Included in thesubstituted ammonium salts that can be employed are themonoethanolammonium, diethanolammonium, triethanolammonium,methylammonium, dimethylammonium, trimethylammonium,tetramethylammonium, morpholinium, N-methylmonoethanolammonium andN-ethylmonoethanolammonium salts and mixtures thereof.

The utility of the compounds of the present invention is not onlyreflected in terms of excellent building and biodegradability propertiesbut also in low cost of preparation, since they are prepared fromreadily available and inexpensive materials. For example, the compoundscontemplated in this invention are derived from sulfomaleic anhydrideand readily available alcohols, thiols, hydroxy acids and amines.

More specifically, the compounds contemplated in this invention arereaction products derived at least in part from sulfomaleic acid orsulfomaleic acid with compounds having an active hydrogen atom.

Compounds having an active hydrogen and suitable for use in preparingthe builders of the present invention are mono- di- or polyhydricalcohols and mono- di- or polyhydroxy acids and their sulfur-containinganalogs. Suitable examples of the aforementioned monohydric alcoholsinclude alkoxyalkanols such as methoxyethanol and the linear primary andsecondary alcohols containing up to 30 carbon atoms and their thioanalogs; aromatic alcohols particularly the carbocyclic mono- andbicyclic aromatic alcohols, such as naphthols and phenols and the mono-di- or tri- C₁ -C₄ alkyl ring substituted derivatives thereof. Suitableexamples of dihydric alcohols include the glycols such as ethyleneglycol, propylene glycol, butylene glycol, trimethylene glycol,tetramethylene glycol, pentamethylene glycol, hexamethylene glycol,heptamethylene glycol, long chain 1,2-diols containing from 8-30 carbonatoms and aromatic carbocyclic glycols such as phenylethylene glycol.Similarly, suitable polyhydric alcohols include glycerol,pentaerythritol, hexanetriol, sugars and their thio analogs.

In addition to the alcohols, the hydroxy carboxylic and sulfonic acids(in their ester and acid/salt forms, respectively) may also react withsulfomaleic anhydride and sulfomaleic acid. These include glycollic,lactic, glyceric, hydroxypropionic, salicyclic and mercapto acetic acid,hydroxymethanesulfonic acid and hydroxyethanesulfonic acid.

Still another important class of compounds containing active hydrogensare ethylene oxide adducts of C₁ to C₃₀ primary and secondary alcoholswith 1-15 moles of ethylene oxide.

In general, the α-substituted-β-sulfosuccinate salts, wherein theα-substituent is joined to the α-carbon atom of the sulfosuccinatemoiety by an O or S linkage, may be prepared by heating at a temperatureof from about 25° to 120°C, and preferably 60° to 100°C, sulfomaleicanhydride with a compound having an active hydrogen followed by furthertreatment with an alkali metal hydroxide. The desired α-oxy orα-thio-β-sulfosuccinate may then be recovered and purified usingconventional techniques.

The α-substituted-β-sulfosuccinate salts wherein the α-substituent isjoined to the α-carbon atom of the sulfosuccinate moiety by an SO or SO₂linkage may be prepared by treating the appropriate α-substitutedthio-β-sulfosuccinate with hydrogen peroxide according to the methodsdescribed on pages 471-472 in the text, "Reagents for Organic Synthesis"by Fieser and Fieser, published by John Wiley & Sons, Inc., 1967,incorporated by reference herein.

The α-substituted-β-sulfosuccinate salts wherein the α-substituent isjoined to the α-carbon atom of the sulfosuccinate moiety by an aminofunction (Formula II) may be prepared by reacting an appropriatelysubstituted or unsubstituted primary or secondary amine with alkalimetal salts of sulfomaleic acid. Typical amines suitable for reaction toform the α-substituted amino-β-sulfosuccinates include:

ethanolamine

diethanolamine

propanolamine

morpholine

N-methylethanolamine

glycine

alanine

N-methyl taurine

alkylamines containing 1-20 carbons in the alkyl chain, as well as otheramines having a replaceable or active hydrogen and a basicity comparableto the aforementioned amines.

In particular the α-amino substituted-β-sulfosuccinates derived fromwater-soluble amines may be prepared by reacting in aqueous solutionwithout the aid of heat and those derived from water-insoluble amines(i.e., higher alkylamines) are reacted in a mixed solvent system such asethanol/water or dioxane/water at temperatures ranging from about 25°Cto about 80°C; isolation from the reaction medium, and purification ifdesired, being effected by conventional methods.

The compounds of Formula III may be prepared by reacting the tertiaryamine compounds of Formula II with oxidizing agents such as hydrogenperoxide, peroxyacetic and peroxyformic acid in the manner described foroxidizing tertiary amines by Hoh et al., J. Am. Oil Chemists' Soc., 40,268 (1963).

In preparing the sulfosuccinate salts from the free acid, the amount ofbase utilized will determine whether the mono- di- or tri-salt isobtained. For example, the use of one mole of base (i.e., sodiumhydroxide) per mole of α-hydroxy-β-sulfosuccinic acid yields themonosodium salt; the use of two moles of sodium hydroxide, the disodiumsalt and the use of three moles of sodium hydroxide, the trisodium salt.When R is carboxymethyl, carboxyethyl, sulfomethyl or sulfoethyl, atetrasalt can also be obtained. Similarly, other bases, such as ammoniumhydroxide and organic amines, may be utilized in the same manner toafford the type of salt desired.

According to the present invention, excellent cleaning results can beobtained by using the builders described above with a wide range ofdetergent surface active materials and mixtures thereof in any of theusual physical forms for such compositions such as powders, beads,flakes, bars, tablets, noodles, liquids and the like. The builders canbe used singularly, in combination with each other as the sole builderin the detergent composition or in combination with other well-knowndetergent builders such as sodium nitrilotriacetate, sodiumethylenediaminetetraacetate, sodium tripolyphosphate, trisodiumorthophosphate, sodium and potassium pyrophosphate, sodium polyacrylate,disodium oxydiacetate, trisodium citrate, trisodiumcarboxymethyloxysuccinate, salts of oxidized starches and sodium orpotassium carbonate, as well as other conventional organic and inorganicbuilders.

When using the detergent compositions of the invention to wash clothes,the wash solutions should have a pH from about 7 to 12 and preferablyfrom about 9 to 11 throughout the washing cycle. Therefore, the presenceof an alkaline buffer in the detergent composition is usually desirableparticularly when the soil to be removed from the clothes has a highcontent of acidic components. Suitable buffers include any of the commonorganic and/or inorganic buffers such as monoethanolamine,diethanolamine, triethanolamine, sodium and potassium silicates, sodiumand potassium carbonates and bicarbonates and the like.

In the detergent compositions of the present invention, the onlyessential ingredients are the detergent surface active material and thebuilder. The weight percent of the builder present in the detergentcomposition will range from about 5 to about 90% and preferably fromabout 20 to about 60% and more preferably 35-50% by weight of the totalweight of the composition. When expressed as a weight ratio of builderto surfactant, the builders used in the instant invention will generallybe present in a ratio of about 1:10 to about 10:1, and preferably 2:1 to5:1 depending on the end use or whether a heavy-duty or light-dutydetergent is desired. When the builders are used in mechanicaldishwashing compositions, the ratio of builder to surfactant is fromabout 10:1 to about 50:1.

The detergent surface active compounds which can be used within thecompositions of this invention include anionic, nonionic, zwitterionic,ampholytic detergent compounds and mixtures thereof. These suitablesubstances are outlined at length below.

a. Anionic detergent compositions which can be used in the compositionsof this invention include both soap and non-soap detergent compounds.Examples of suitable soaps are the sodium, potassium, ammonium andalkylolammonium salts of higher fatty acids (C₁₀ -C₂₀). Particularlyuseful are the sodium or potassium salts of the mixtures of fatty acidsderived from coconut oil and tallow, i.e., sodium or potassium tallowand coconut soap and tall oil. Examples of anionic organic non-soapdetergent compounds are the water soluble salts, alkali metal salts oforganic sulfuric reaction products having in their molecular structurean alkyl radical containing from about 8 to about 22 carbon atoms and aradical selected from the group consisting of sulfonic acid and sulfuricacid ester radicals. Important examples of the synthetic detergentswhich form a part of the compositions of the present invention are thesodium or potassium alkyl sulfates especially those obtained bysulfating the higher alcohols (C₈ -C₁₈ carbon atoms) produced byreducing the glycerides of tallow or coconut oil; sodium or potassiumalkyl benzensulfonates in which the alkyl group contains from about 9 toabout 20 carbon atoms and in which the alkyl group is attached to thebenzene ring in either the one position or at the secondary positionssuch as in LAS,* sodium p-(2-dodecyl-)benzenesulfonate, sodiump-(2-octadecyl)benzenesulfonates and sodiump-(3-dodecyl)benzenesulfonate; sodium alkyl glyceryl ether sulfonates,especially those ethers of the higher alcohols derived from tallowcoconut oil and synthetic alcohols derived from petroleum; sodiumcoconut oil fatty acid monoglyceride sulfates and sulfonates; sodium orpotassium salts of sulfuric acid esters and carboxymethylatedderivatives of the reaction product of one mole of a higher fattyalcohol (e.g., tallow or coconut oil alcohols) and about 1 to 6 moles ofethylene oxide per molecule and in which the alkyl radicals containabout 9 to about 18 carbon atoms; the reaction product of fatty acidsesterified with isethionic acid and neutralized with sodium hydroxidewhere, for example, the fatty acids are derived from coconut oil; sodiumor potassium salts of fatty acid amides of methyl taurine in which thefatty acids, for example, are derived from coconut; alkane sulfonatessuch as those derived by reacting alpha-olefins containing 8 to 20carbon atoms with sodium bisulfite and those derived by reactingparaffins with SO₂ and Cl₂ and then hydrolyzing with a base to produce arandom sulfonate; alpha-olefin sulfonates such as those derived byreacting alpha-olefins with SO₃ and then neutralizing the reactionproduct; and others known in the art.

b. Nonionic synthetic detergents may be broadly defined as compoundswhich do not ionize in water solution. For example, a well-known classof nonionic synthetic detergents is made available on the market underthe trade name of "Pluronic." These compounds are formed by condensingethylene oxide with an hydrophobic base formed by the condensation ofpropylene oxide with propylene glycol. The hydrophobic portion of themolecule which, of course, exhibits water insolubility has a molecularweight of from about 1,500 to 1,800. The addition of polyoxyethyleneradicals to this hydrophobic portion tends to increase the watersolubility of the molecule as a whole and the liquid character of theproduct is retained up to the point where polyoxyethylene content isabout 50% of the total weight of the condensation product.

Other suitable nonionic synthetic detergents include:

1. The polyethylene oxide condensates of alkylphenols, e.g., thecondensation products of alkylphenols having an alkyl group containingfrom about 6 to 12 carbon atoms in either a straight chain or branchedchain configuration, with ethylene oxide, the said ethylene oxide beingpresent in amounts equal to 5 to 25 moles of ethylene oxide per mole ofalkylphenols. The alkyl substituent in such compounds may be derivedfrom polymerized propylene, disobutylene, octene, dodecene, or nonene,for example.

2. Those derived from the condensation of ethylene oxide with theproduct resulting from the reaction of propylene oxide andethylenediamine. For example, compounds containing from about 40% toabout 80% polyoxyethylene by weight and having a molecular weight offrom about 5,000 to about 11,000 resulting from the reaction of ethyleneoxide groups with a hydrophobic base constituted of the reaction productof ethylene diamine and excess propylene oxide, said hydrophobic basehaving a molecular weight of the order of 2,500 to 3,000 aresatisfactory.

3.The condensation product of aliphatic alcohols, primary or secondary,having from 8 to 18 carbon atoms, in either straight chain or branchedconfiguration, with ethylene oxide, e.g., a coconut alcohol-ethyleneoxide condensate having from 6 to 30 moles of ethylene oxide per mole ofcoconut alcohol, the coconut alcohol fraction having from 10 to 14carbon atoms; a C₁₁ -C₁₅ random secondary alcohol derived fromn-paraffins and condensed with 7 moles of ethylene oxide per mole ofsecondary alcohol.

4.Long chain tertiary amine oxides corresponding to the followinggeneral formula, R₁ R₂ R₃ N→O, wherein R₁ is an alkyl radical of fromabout 8 to 18 carbon atoms and R₂ and R₃ are each methyl, ethyl orhydroxy ethyl radicals. The arrow in the formula is a conventionalrepresentation of a semi-polar bond. Examples of amine oxides suitablefor use in this invention include dimethyloctylamine oxide,dimethyldecylamine oxide, dimethyldodecylamine oxide,dimethyltetradecylamine oxide and dimethylhexadecylamine oxide,N-bis(hydroxyethyl)dodecylamine oxide.

5. Long chain tertiary phosphine oxides corresponding to the followingformula RR'R"P→O, wherein R is an alkyl, alkenyl or monohydroxyalkylradical ranging from 10 to 18 carbon atoms in chain length and R' and R"are each alkyl or monohydroxyalkyl groups containing from 1 to 3 carbonatoms. The arrow in the formula is a conventional representation of asemi-polar bond. Examples of suitable phosphine oxides are:

dimethyldodecylphosphine oxide,

dimethyltetradecylphosphine oxide,

ethylmethyltetradecylphosphine oxide,

cetyldimethylphosphine oxide,

dimethylstearylphosphine oxide,

cetylethylpropylphosphine oxide,

diethyldodecylphosphine oxide,

diethyltetradecylphosphine oxide,

bis(hydroxymethyl)dodecylphosphine oxide,

bis (2-hydroxyethyl)dodecylphosphine oxide,

2-hydroxypropylmethyltetradecylphosphine oxide,

dimethyloleylphosphine oxide, and

dimethyl-2-hydroxydodecylphosphine oxide.

6. Dialkyl sulfoxides corresponding to the following formula, RR'S→O,wherein R is an alkyl, alkenyl, beta- or gamma-monohydroxyalkyl radicalor an alkyl or beta- or gamma-monohydroxyalkyl radical containing one ortwo other oxygen atoms in the chain, the R groups ranging from 10 to 18carbon atoms in chain length, and wherein R' is methyl, ethyl oralkylol. Examples of suitable sulfoxide compounds are:

dodecyl methyl sulfoxide

tetradecyl methyl sulfoxide

3-hydroxytridecyl methyl sulfoxide

2-hydroxydodecyl methyl sulfoxide

3-hydroxy-4-decyloxybutyl methyl sulfoxide

3-hydroxy-4dodecylcoxybutyl methyl sulfoxide

2-hydroxy-3-decyloxypropyl methyl sulfoxide

2-hydroxy-3-dodecyloxypropyl methyl sulfoxide

dodecyl ethyl sulfoxide

2 -hydroxydodecyl ethyl sulfoxide

doedcyl-2-hydroxy ethyl sulfoxide

c. Ampholytic synthetic detergents can be broadly described asderivatives of aliphatic secondary and tertiary amines, in which thealiphatic radical may be straight chain or branched and wherein one ofthe aliphatic substituents contains from about 8 to 18 carbon atoms andone contains an anionic water solubilizing group. Examples of compoundsfalling within this definition are sodium-3-dodecylaminopropionate andsodium-3-dodecylaminopropanesulfonate and sodiumN-2-hydroxydodecyl-N-methyl-taurate.

d. Zwitterionic synthetic detergents can be broadly described asderivatives of aliphatic quaternary ammonium compounds, sulfoniumcompounds and phosphonium compounds in which the aliphatic radical maybe straight chain or branched and wherein one of the aliphaticsubstituents contains from about 8 to 18 carbon atoms and one containsan anionic water solubilizing group. Examples of compounds fallingwithin this definition are3-(N,N-dimethyl-N-hexadecylammonio)propane-1-sulfonate,3-(N,N-dimethyl-N-hexadecylammonio)-2-hydroxypropane-1-sulfonate,3-(dodecylmethylsulfonium) propane sulfonate, and3-(cetylmethylphosphonium)ethane sulfonate.

Other materials which may be present in the detergent compositions ofthe invention in generally minor amounts are those conventionallypresent therein. Typical examples thereof include the well-knownsoil-suspending agents, hydrotropes, corrosion inhibitors, dyes,perfumes, fillers such as sodium sulfate, optical brighteners,perborates, bleaches, bleach activators, enzymes, suds boosters, sudsdepressants, germicides, fungicides, anti-tarnishing agents, cationicdetergents, fabric softening agents and in the case of liquidcompositions, opacifiers and organic solvents. The balance of thedetergent compositions may be water or inert filler.

It has been discovered that when higher than normal levels of anionic,nonionic, ampholytic or zwitterionic surfactants are used with thesulfosuccinate derivative salts of this invention, the detergency of theformulation is significantly enhanced particularly at low formulationconcentration (˜0.18) which are typically used by the U.S. housewife.For enhanced results the detergent formulation should contain surfactantlevels of about 25% to about 45% by weight and the sulfosuccinatederivative salt levels of about 25% to about 75% by weight in the caseswhere the surfactants are anionic, ampholytic or zwitterionic. When thesurfactant is a nonionic, enhanced detergency results are obtained whenthe level of said nonionic in the formulation is from about 15% to 30%by weight and the level of sulfosuccinate derivative salt is from about25% to about 85% by weight.

In addition to their use in general household detergent compositions,the builders of the present invention find utility as boiler scaleremovers, stain removers and general chelating agents. When used at pH'sof about 2 to about 5 as partially neutralized alkali metal, ammonium orsubstituted ammonium salts, especially in combination with wettingagents and surfactants, the compounds of the invention are excellentmetal cleaning compounds.

Table 1 further illustrates the present invention. The detergentformulations set forth in the Table represent detergent compositionscontaining the builders of the present invention in combination withrepresentative classes of surface active agents compared with control orstandard phosphate built detergent compositions. The compositions wereprepared by blending together the recited components in the proportionsindicated, including an anticorrosive agent and buffer agent (sodiumsilicate). The compositions were then tested on vacuum cleaner dustsoiled cloth for detergency or cleaning ability in the Terg-O-Tometertest; wherein washing conditions are as indicated and the resultsreported as detergency units. The average detergency units (DU) of theformulation is the final reflectance value of the washed cloth (averageof 2 runs) minus the initial reflectance of the soiled cloth, thereflectances being obtained by measurement with a Gardner automaticcolor difference meter, Model AC-3.

                                      TABLE 1                                     __________________________________________________________________________    Component      % Composition                                                  __________________________________________________________________________    α-hydroxy.sup.a                                                                        50  50  50  50  50                                             α-(2-hydroxy-                50  50                                     ethoxy).sup.a                                                                 α-dodecyloxy.sup.a                   50                                 α-methoxy.sup.a                          50                             α-carboxymethoxy.sup.a                       50                         α-dodecyloxyethoxy.sup.a                         50                     α-dodecylthio.sup.a                                                     Na.sub.5 P.sub.3 O.sub.10                                                     Sodium silicate                                                                              10  10  10  10  10  10  10  10  10  10  10  10                 (SiO.sub.2 :Na.sub.2 O=                                                       2.4:1)                                                                        Anionic.sup.b  18                  18  36  18  18  18  18  18                 Anionic.sup.c      18                                                         Nonionic.sup.d         20                                                     Ampholytic.sup.e           18                                                 Zwitterionic.sup.f             18                                             Water          ←bal →                                             Formulation     0.2                                                                               0.2                                                                               0.2                                                                               0.2                                                                               0.2                                                                               0.2                                                                               0.1                                                                               0.2                                                                               0.2                                                                               0.2                                                                               0.2                                                                               0.2               Concentration, %                                                              Detergency (DU's)                                                                            24.6                                                                              24.4                                                                              26.5                                                                              23.1                                                                              25.6                                                                              26.1                                                                              24.7                                                                              27.1                                                                              23.0                                                                              24.2                                                                              15.4                                                                              22.3               __________________________________________________________________________    Component      Controls (% Composition)                                       __________________________________________________________________________    α-hydroxy.sup.a                                                         α-(2-hydroxy-                                                           ethoxy).sup.a                                                                 α-dodecyloxy.sup.a                                                      α-methoxy.sup.a                                                         α-carboxymethoxy.sup.a                                                  α-dodecyloxyethoxy.sup.a                                                α-dodecylthio.sup.a              50  50  50                             Na.sub.5 P.sub.3 O.sub.10                                                     Sodium Silicate                                                                              10  10  10  10  10  10  10  10  10                             (SiO.sub.2 :Na.sub.2 O =                                                      2.4:1)                                                                        Anionic.sup.b  18  18                                                         Anionic.sup.c          18              18                                     Nonionic.sup.d             20              20                                 Ampholytic.sup.e               18              18                             Zwitterionic.sup.f                 18                                         Water          ←bal →                                             Formulation     0.1                                                                               0.2                                                                               0.2                                                                               0.2                                                                               0.2                                                                               0.2                                                                               0.2                                                                                0.2                                                                              0.2                           Concentration, %                                                              Detergency (DU's)                                                                             4.8                                                                               6.4                                                                              16.1                                                                              19.9                                                                              18.8                                                                              20.1                                                                              28.7                                                                              29.4                                                                              28.5                           __________________________________________________________________________     .sup.a Sodium salts of α-substituted-β-sulfosuccinate              .sup.b Sodium linear secondary alkyl (C.sub.10 --C.sub.15) benzene            sulfonate                                                                     .sup.c Sodium C.sub.15 --C.sub.18 α-olefin sulfonate                    .sup.d C.sub.11 --C.sub.15 linear secondary alcohols ethoxylated with 7       moles ethylene oxide/mole alcohol                                             .sup.e C.sub.14 --C.sub.16 HAMT (sodium hydroxyalkyl N-methyl taurate)        .sup.f Sulfobetaine DCH (cododimethylsulfopropyl betaine)                     Washing conditions - 180 ppm (2:1 Ca.sup.+.sup.+/Mg .sup.+.sup.+);            120°F: pH 10                                                      

EXAMPLE 1 Preparation of Trisodium α-Hydroxy-β-Sulfosuccinate

Sulfomaleic anhydride was prepared by heating a mixture of 1 mole ofsulfur trioxide with 1 mole of maleic anhydride first at 60°C until theexothermic reaction subsided and then at 100°-110°C for 3 hours.Forty-five gm of sulfomaleic anhydride product was then mixed with 45 gmof icc and the resulting solution extracted 25 times with 50 ml portionsof ether to remove maleic acid. A 20 ml portion of the resulting aqueousphase was collected, adjusted to pH = 11 with calcium hydroxide andrefluxed for 4 hours. NMR analysis indicated that all of the sulfomaleicacid had hydrated within the first hour of reflux. The reaction mixturewas then passed through a column of cation exchange resin. A portion ofthe effluent was then neutralized to pH = 8.5 and evaporated to a whitecrystalline residue (19.2 gm), which contained 80.9% of trisodiumα-hydroxy-β-sulfosuccinate as determined by NMR analysis (using D₂ Osolvent and K biphthalate as an internal standard) and 10.4% water byKarl Fischer analysis.

EXAMPLE 2 α-Thiosubstituted-β-Sulfosuccinates

The procedure of Example 1 is repeated except that in place of Ca(OH)₂the pH is adjusted to 8.6 with NaOH. Then, an aqueous solutioncontaining excess sodium hydrosulfide, sodium methyl mercaptide orsodium ethyl mercaptide is added and the resulting solution allowed tostand overnight. The reaction mixture is then passed through a column ofcation exchange resin and the effluent evaporated to low volume. The pHis the adjusted to 8.5 with sodium hydroxide and the solution evaporatedto dryness. In this way, there is afforded respectively:

trisodium α-mercapto-β-sulfosuccinate

trisodium α-methylthio-β-sulfosuccinate

trisodium α-ethylthio-β-sulfosuccinate

EXAMPLE 3 Preparation of Trisodium α-Methoxy-β-Sulfosuccinate

Sulfomaleic anhydride, 3.9 gm, was dissolved in 25 ml of methanol andrefluxed for 5 hours. Then, 24 gm of 25% sodium methoxide in methanolwas added and the solution was refluxed for 2 hours. The methanol wasthen evaporated and the residue was dissolved in 100 ml of water andheated for 1 hour at 80°C. The solution was then decolorized with 5 gmof charcoal, filtered and evaporated. The crude residue of trisodiumα-methoxy-β-sulfosuccinate was purified by trituration with acetic acidand then filtered, washed with acetone and dried.

α-ethoxy-β-sulfosuccinate may be prepared by substituting ethanol andsodium ethoxide in the procedure described above.

EXAMPLE 4 Preparation of Trisodium α-Dodecyloxy-β-Sulfosuccinate

Sulfomaleic anhydride (10 gm) are mixed with 80 gm (0.45 mole) ofn-dodecanol and heated at 100°C for 14 hours. A solution of 7.04 gm ofsodium hydroxide in 50 ml water is then added and the mixture heated at60°C for 2 hours. The heated mixture is then extracted three times with300 cc portions of acetone (at reflux) and the acetone insolublefraction is then filtered, washed with additional acetone and dried togive 16.2 gm of the title compound (structure confirmed by NMR and ionexchange of a sample followed by titration with standard sodiumhydroxide: neutralization equivalent: found 147.0, theory 149.3).

EXAMPLE 5 Preparation of Trisodium α-Dodecyloxyethoxy-β-Sulfosuccinate

Using the procedure of Example 4 and substituting 37 gm (0.32 mole) of2-dodecyloxyethanol in place of the n-dodecanol there is obtainedtrisodium α-dodecyloxyethoxy-β-sulfosuccinate.

EXAMPLES 6-8

Using n-tetradecanol in place of n-dodecanol in the procedure of Example4 and carrying out the hydrolysis step with 10% excess aqueous sodiumhydroxide at 80°C for 4 hours instead of 60°C at 2 hours, there isobtained trisodium α-tetradecyloxy-β-sulfosuccinate (Example 6).Similarly, using n-hexadecanol in place of n-dodecanol, there isobtained trisodium α-hexadecyloxy-β-sulfosuccinate (Example 7); usingn-octadecanol, there is obtained trisodiumα-octadecyloxy-β-sulfosuccinate (Example 8).

EXAMPLE 9 Preparation of Trisodium α-Hydroxyethoxy-β-Sulfosuccinate

Sulfomaleic anhydride (20 gm) is mixed with 37.2 gm (0.6 mole) ofethylene glycol and heated at 80°C for 4 hours. A solution of 16 gm (0.4mole) of sodium hydroxide in 75 ml of water is then added and themixture heated at 80°C for 4 hours. The mixture is then mixed withacetone to precipitate trisodium α-hydroxyethoxy-β-sulfosuccinate, whichis purified by repeated extractions with hot acetone to remove allethylene glycol and water followed by filtration and drying in an oven.

EXAMPLE 10 Preparation of the Tetrasodium Salt ofα-Carboxymethyloxy-β-Sulfosuccinic Acid

Sulfomaleic anhydride (19.4 gm) is heated to 60°C and combined with 76gm of ethyl glycolate. After heating the mixture at 80°C for 5 1/2hours, there is added a solution of 45 gm of sodium hydroxide dissolvedin 135 gm of water and heating is continued at 80° for an additional 3hours. The mixture is then diluted with water and passed through acolumn of a cation exchange resin. The resulting eluent is thenevaporated in vacuo to a low volume and the concentrate extractedrepeatedly with acetone to remove glycolic acid and other impurities.The resulting extracted residue is then dissolved in water and the pH ofthe solution adjusted to 8.6 with dilute sodium hydroxide. Evaporationof the solution in vacuo and drying over P₂ O₅ gives a residue of thetetrasodium salt of α-carboxymethyloxy-β-sulfosuccinic acid.

EXAMPLE 11 Preparation of Trisodiumα-(2-Hydroxyethylamino)-β-Sulfosuccinate

Sulfomaleic anhydride (prepared from a 1/1 mole ratio of SO₃ /maleicanhydride by heating the mixture at 100°-110°C for 3 hours; activecontent, 86%), 20.7 gm (0.1 mole), was added to 100 gm of ice. Theresulting solution was kept at 10°-15°C and neutralized to pH = 8.6 byslowly adding 28.4 gm of 50% sodium hydroxide. Monoethanolamine, 6.1 gm(0.1 mole), was next added slowly and the temperature allowed to rise toroom temperature. After standing overnight, the reaction mixture waspoured into 800 ml of acetone. The solvent was then decanted from theresulting syrupy lower layer and the latter reprecipitated three timesfrom water with fresh acetone. The residue was then dried in adessicator over P₂ O₅ to give 38.8 gm of an off-white, granular productcontaining approximately 88% trisodiumα-(12-hydroxyethylamino)-β-sulfosuccinate by titration with perchloricacid. The structure was confirmed by NMR analysis.

The above method is satisfactory for reacting water-soluble aminocompounds with sulfomaleic anhydride. For water insoluble aminocompounds such as the higher alkyl amines, a mixed solvent system suchas ethanol/ water and dioxane/water is used together with temperaturesin the range of 25°-80°C.

Table 2 indicates the reactants and procedure required to obtain otherα-substituted-β-sulfosuccinate salts having the R and Z moieties setforth in Formula I.

                                      TABLE 2                                     __________________________________________________________________________    R                  Z    Example                                                                            Reactants (Sulfomaleic Anhydride                 __________________________________________________________________________                                 +)                                               H                  O    1    Water                                            Alkyl (C.sub.1 --C.sub.2)                                                                        O    3    C.sub.1 or C.sub.2 alcohol                       Alkyl (C.sub.3 --C.sub.30)                                                                       O    4-8  C.sub.3 --C.sub.30 primary, secondary or                                      tertiary                                                                      alcohol                                          Phenyl             O    4-8  Phenol                                           Carboxyphenyl      O    10   Methyl salicylate                                Alkylphenyl        O    4-8  Alkylphenol                                      o, m, p methylphenyl                                                                             O    4-8  o, m, p cresol, carvacrol, thymol                HOOC--CH.sub.2 --  O    10   Ethyl glycolate                                  HOOC--CH.sub.2 CH.sub.2 --                                                                       O    10   Methyl-β-hydroxypropionate                  HO.sub.3 S--CH.sub.2 CH.sub.2 --                                                                 O    4    Isethionic acid                                  R'O(CH.sub.2 CH.sub.2 O).sub.n --CH.sub.2 CH.sub.2 --                                            O    4    R'O(CH.sub.2 CH.sub.2 O).sub.n CH.sub.2                                       CH.sub.2 OH                                      HOCH.sub.2 CH.sub.2 OCH.sub.2 CH.sub.2 --                                                        O    4    HOCH.sub.2 CH.sub.2 OCH.sub.2 CH.sub.2 OH        HO(CH.sub.2 CH.sub.2 O).sub.3 CH.sub.2 CH.sub.2 --                                               O    4    HO(CH.sub.2 CH.sub.2 O).sub.3 CH.sub.2                                        CH.sub. 2 OH                                     HO(CH.sub.2 CH.sub.2 O).sub.10 CH.sub.2 CH.sub.2 --                                              O    4    HO(CH.sub.2 CH.sub.2 O).sub.10 CH.sub.2                                       CH.sub.2 OH                                      HO(CH.sub.2 CH.sub.2 O).sub.15 CH.sub.2 CH.sub.2 --                                              O    4    HO(CH.sub.2 CH.sub.2 O).sub.15 CH.sub.2                                       CH.sub.2 OH                                      CH.sub.3 CH.sub.2 O(CH.sub.2 CH.sub.2 O).sub.3 CH.sub.2 CH.sub.2 --                              O    4    CH.sub.3 CH.sub.2 O(CH.sub.2 CH.sub.2                                         O).sub.3 CH.sub.2 CH.sub.2 OH                    CH.sub.3 (CH.sub.2).sub.10 O(CH.sub.2 CH.sub.2 O).sub.9 CH.sub.2 CH.sub.2     --                 O    4    CH.sub.3 (CH.sub.2).sub.10 O(CH.sub.2                                         CH.sub.2 O).sub.9 CH.sub.2 CH.sub.2 OH           CH.sub.3 (CH.sub.2).sub.20 O(CH.sub.2 CH.sub.2 O).sub.3 CH.sub.2 CH.sub.2     --                 O    4    CH.sub.3 (CH.sub.2).sub.20 O(CH.sub.2                                         CH.sub.2 O).sub.3 CH.sub.2 CH.sub.2 OH           CH.sub.3 CH.sub.2 S(CH.sub.2 CH.sub.2 O).sub.3 CH.sub.2 CH.sub.2 --                              O    4    CH.sub.3 CH.sub.2 S(CH.sub. 2 CH.sub.2                                        O).sub.3 CH.sub.2 CH.sub.2 OH                    CH.sub.3 CH.sub.2 S(CH.sub.2 CH.sub.2 O).sub.9 CH.sub.2 CH.sub.2 --                              O    4    CH.sub.3 CH.sub.2 S(CH.sub.2 CH.sub.2                                         O).sub.9 CH.sub.2 CH.sub.2 OH                    HOCH.sub.2 CH.sub.2 --                                                                           O    9    Ethylene glycol                                  HOCH.sub.2 CH.sub.2 CH.sub.2 --                                                                  O    9    Trimethylene glycol                              HOCH.sub.2 (CH).sub.4 CH.sub.2 --                                                                O    9    Hexamethylene glycol                             H                  S    2    Sodium hydrosulfide                              Alkyl (C.sub.1 --C.sub.2)                                                                        S    2    Sodium (C.sub.1 --C.sub.2) alkyl mercaptide      Alkyl (C.sub.3 --C.sub.30)                                                                       S    4-8  C.sub.3 --C.sub.30 alkylmercaptan                Phenyl             S    4-8  Thiophenol                                       Carboxyphenyl      S    10   Methyl 2-mercaptobenzoate                        Alkylphenyl        S    4-8  Alkylthiophenol                                  HOOC--CH.sub.2 --  S    10   Ethyl mercaptoacetate                            HOOC.sub.2 --CH.sub.2 --CH.sub.2 --                                                              S    10   Methyl β-mercaptopropionate                 HO.sub.3 SCH.sub.2 CH.sub.2 --                                                                   S    4    Mercaptoethanesulfonic acid                      R'O(CH.sub.2 CH.sub.2 O).sub.n CH.sub.2 CH.sub.2 --                                              S    4    RO(CH.sub.2 CH.sub.2 O).sub.n CH.sub.2                                        CH.sub.2 SH                                      HOCH.sub.2 CH.sub. 2 OCH.sub.2 CH.sub.2 --                                                       S    2    HOCH.sub.2 CH.sub.2 OCH.sub.2 CH.sub.2 SNa       HO(CH.sub.2 CH.sub.2 O).sub.3 CH CH--                                                            S    2    HO(CH.sub.2 CH.sub.2 O).sub.3 CH.sub.2                                        CH.sub.2 SNa                                     HO(CH.sub.2 CH.sub.2 O).sub.10 CH.sub.2 CH.sub.2 --                                              S    2    HO(CH.sub.2 CH.sub.2 O).sub.10 CH.sub.2                                       CH.sub.2 SNa                                     HO(CH.sub.2 CH.sub.2 O).sub.15 CH.sub.2 CH.sub.2 --                                              S    2    HO(CH.sub.2 CH.sub.2 O).sub.15 CH.sub.2                                       CH.sub.2 SNa                                     CH.sub.3 CH.sub.2 O(CH.sub.2 CH.sub.2 O).sub.3 CH.sub.2 CH.sub.2 --                              S    4    CH.sub.3 CH.sub.2 O(CH.sub.2 CH.sub.2                                         O).sub.3 CH.sub.2 CH.sub.2 SH                    CH.sub.3 (CH.sub.2).sub.11 O(CH.sub.2 CH.sub.2 O).sub.9 CH.sub.2 CH.sub.2     --                 S    4    CH.sub.3 (CH.sub.2).sub.11 ((CH.sub.2                                         CH.sub.2 O).sub.9 CH.sub.2 CH.sub.2 SH           CH.sub.3 (CH.sub.2).sub.21 O(CH.sub.2 CH.sub.2 O).sub.3 CH.sub.2 CH.sub.2     --                 S    4    CH.sub.3 (CH.sub.2).sub.21 O(CH.sub.2                                         CH.sub.2 O).sub.3 CH.sub.2 CH.sub.2 SH           CH.sub.3 CH.sub. 2 S(CH.sub.2 CH.sub.2 O).sub.3 CH.sub.2 CH.sub.2                                S-   4    CH.sub.3 CH.sub.2 S(CH.sub.2 CH.sub.2                                         O).sub.3 CH.sub.2 CH.sub.2 SH                    CH.sub.3 CH.sub.2 S(CH.sub.2 CH.sub.2 O).sub.9 CH.sub.2 CH.sub.2 --                              S    4    CH.sub.3 CH.sub.2 S(CH.sub.2 CH.sub.2                                         O).sub.9 CH.sub.2 CH.sub.2 SH                    HOCH.sub.2 CH.sub.2 --                                                                           S    2    Sodium 2-hydroxyethylmercaptide                  HOCH.sub.2 CH.sub.2 CH.sub.2 --                                                                  S    2    Sodium 3-hydroxypropylmercaptide                 HOCH.sub.2 (CH.sub.2).sub.4 CH.sub.2 --                                                          S    2    Sodium 6-hydroxyhexylmercaptide                  Alkyl (C.sub.1 --C.sub.2)                                                                        SO   2    C.sub.1 --C.sub.2 alkylmercaptan.sup.a           Alkyl (C.sub.3 --C.sub.30)                                                                       SO   4-8  C.sub.3 --C.sub.30 alkylmercaptan.sup.a          Phenyl             SO   4-8  Thiophenol.sup.a                                 Carboxyphenol      SO   10   Methyl 2-mercaptobenzoate.sup.a                  C.sub.1 --C.sub.4 alkylphenyl                                                                    SO   4-8  Alkylthiophenol.sup.a                            HOOC--CH.sub.2 --  SO   10   Ethylmercaptoacetate.sup.a                       HOOC--CH.sub.2 CH.sub.2 --                                                                       SO   10   Methyl β-mercaptopropionate.sup.a           R'O(CH.sub.2 CH.sub.2 O).sub.n CH.sub.2 --                                                       SO   5    R'O(CH.sub.2 CH.sub. 2 O).sub.n CH.sub.2                                      CH.sub.2 SH.sup.a                                HOCH.sub.2 CH.sub.2 --                                                                           SO   2    Sodium 2-hydroxyethylmercaptide                  HOCH.sub.2 CH.sub.2 CH.sub.2 --                                                                  SO   2    Sodium 3-hydroxypropylmercaptide                 HO(CH.sub.2 CH.sub.2).sub.4 CH.sub.2 --                                                          SO   2    Sodium 6-hydroxyhexylmercaptide                  C.sub.1 --C.sub.2 alkyl                                                                          SO.sub.2                                                                           2    C.sub.1 --C.sub.2 alkylmercaptan.sup.b           C.sub.3 --C.sub.30 alkyl                                                                         SO.sub.2                                                                           4-8  C.sub.3 --C.sub.30 alkylmercaptan.sup.b          Phenyl             SO.sub.2                                                                           4-8  Thiophenol.sup.b                                 Carboxyphenyl      SO.sub.2                                                                           4-8  Methyl 2-mercaptobenzoate.sup.b                  HOOC--CH.sub.2 --  SO.sub.2                                                                           10   Ethyl mercaptoacetate.sup.b                      HOOC--CH.sub.2 CH.sub.2 CH.sub.2 --                                                              SO.sub.2                                                                           10   Methyl 2-mercaptobutyrate.sup.b                  R'O(CH.sub.2 CH.sub.2 O).sub.n CH.sub.2 CH.sub.2 --                                              SO.sub.2                                                                           5    R'O(CH.sub.2 CH.sub.2 O).sub.n CH.sub.2                                       CH.sub.2 SH.sup.b                                __________________________________________________________________________     .sup.a Followed by oxidation to sulfoxide according to Fieser reference.      .sup.b Followed by oxidation to sulfone according to Fieser reference.   

What is claimed is:
 1. An α-alkylthio-β-sulfosuccinic acid having thegeneral formula: ##EQU5## and the alkali metal, ammonium,monoethanolammonium, diethanolammonium, triethanolammonium,methylammonium, dimethylammonium, trimethylammonium,tetramethylammonium, morpholinium, N-methylmonoethanolammonium orN-ethylmonoethanolammonium salt thereof wherein R is an alkyl containing1 - 30 carbon atoms.
 2. The α-alkylthio-β-sulfosuccinic acid and saltthereof of claim 1 wherein the alkyl group is methyl.
 3. Theα-alkylthio-β-sulfosuccinic acid and salt thereof of claim 1 wherein thealkyl group is ethyl.
 4. The α-alkylthio-β-sulfosuccinic acid and saltthereof of claim 1 wherein the alkyl group is dodecyl.
 5. Theα-alkylthio-β-sulfosuccinic acid and salt thereof of claim 1 wherein thealkyl group is tetradecyl.
 6. The α-alkylthio-β-sulfosuccinic acid andsalt thereof of claim 1 wherein the alkyl group is hexadecyl.
 7. Theα-alkylthio-β-sulfosuccinic acid and salt thereof of claim 1 wherein thealkyl group is octadecyl.